Michael Phelps' son Boomer is the youngest (and cutest) Team USA fan at the Rio Olympics

RIO DE JANERIO — Michael Phelps' baby was there to see his daddy win his first gold medal of the 2016 Rio Olympics.

Phelps announced Sunday night that he would compete in the 4-by-100-meter freestyle relay just hours before the race began. He was already set to race in Monday night’s 200-meter butterfly.

His family, including son Boomer and fiancée Nicole Johnson, were in the stands cheering him on as Phelps won his first gold medal at this year’s games.

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After the games, Phelps FaceTimed with his baby boy and showed off his new gold medal. Johnson and baby Boomer shared the moment on Instagram.

"There's absolutely nothing in this world like watching your son talk to his daddy on FaceTime. @m_phelps00 was showing @boomerrphelps his gold medal and boomer had SO much to say. #thankyou @mamaphelpsh20 for capturing the moment," Johnson wrote alongside the pic.

Boomer’s own Instagram account has also been pretty active ahead of the Olympic Games. He was all smiles while showing off his stars and stripes and his very own “gold medal” while hanging out with his dad in Rio.

Phelps has a full schedule in Rio. He is set to participate in the 200-meter butterfly on Monday; the 200-meter individual medley on Wednesday; and the 100-meter butterfly on Thursday.

This is his first Olympics since Boomer was born.

(H/T: PEOPLE)